Injection moulding is often used as a method of manufacturing small plastic articles. In such methods, usually small granules of the plastics material are heated so as to melt the material and the resulting fluid is injected at high temperature and pressure, perhaps 300.degree. C. and 2,000 PSI into a mould of a desired shape. The material is then allowed to set in the mould as it cools.
Such a method is satisfactory for the manufacture of small, homogeneous, articles. However, integrated circuit cards or "smart cards", which comprises a number of components such as electronic circuits, input/output interfaces, substrates and labels, are less well suited to the process, since the high pressures and temperatures involved tend to displace inserts and indeed can damage the functioning thereof. Smart cards are therefore generally manufactured by a lamination process or, in the case of contact cards, the electronic circuit is inserted into a recess formed in the surface of a plastic card.